Improvement in steam air-ejectors



LY'. SMITH'.

Steam Ai'r Ejctursl Patented March11,1873.

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IMPROVEMENT IN STEAM AIR-EJECTORS.

Specification forming part of Letters Patent No. 136,780, dated March 1l, 1873.

To all whom it may conce-rn:l

, Be it known that I, JOHN Y. SMITH, residing at Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Ejectors for Ejecting Air from Vessels connected with Car-Brakes, and for other purposes, of which .the following is a specification:

Figure lis an elevation ofmy improved ejector; and Fig. 2 is a sectional elevation, showing the adjustable outer case, the slot therein, the steam-induction pipe, thepassageforthe steam, the air-nozzle, the vacuum-valve, and a dripvalve.

Gorrespondin g letters refer to corresponding parts in both of the figures.

This invention relates to th at class of instruments which are used for forming a vacuum in vessels, pipes, or in other devices where it is necessary; and it consists in the construction, combination, and arrangement of its parts, as will be more fully explained hereinafter.

In constructing devices of this character I form the case A of cast or of sheet metal and provide upon that end thereof into which the iiuid or liquid to be expelled enters a screwthread or other suitable means for attaching thereto a pipe or hose. At a suitable distance from this end ofthe ease a chamber is provided upon the lower or outer wall of which there is formed a valve-seat, as shown in Fig. 2. To the opposite side or wall of this chamber there is attached an air nozzle, A', the length of which is to be such that its opposite end shall extend nearly to the angular portion ofthe section A2 of the outer case. nozzle A1 there is a chamber or steam-space which is formed by the outer wall ofthe section A of the case and the air-nozzle. Into this space steam is admitted through a pipe, B, attached to its surface or to a suitable nozzle thereon. Theadjustable section A2 of the case is to be constructed substantially as shown in Fig. 2, it having upon its inner end a socket, A3, which ts snugly on the end of section A so that it may turn and slide thereon. Upon two sides of this socket there are formed angular slots, as shown at a, in order that as the -section A2 is turned upon section A it shall be moved longitudinally thereon and thusthe distance of its angular portion with reference to the end of the air-discharge nozzle regulated at Outside of the air:

will. The angular portion of section A2 above referred to is to be made of thin sheet metal,

and should present an acute angle to the axis j of the instrument, in order that as the steam passes this point it shall be brought into intimate contact with the thin portion of thecase and kept there as long as possible, in order that time shall 4be given it to be condensed at that point, or, at best, a sufficient portion of it to aid in the production of a vacuum. That portion A4 of this section which is outside of, but connected to, the angular portion A3 is of about the same diameter as the smallest end of said angular portion, in order that the uncondensed steam and the jet of air from the air-nozzle may be carried forward in a compact Y mass into the enlarged portion of this section, j

which portion is provided with a screw-thread or other means for attaching thereto ya pipe or hose. When the adjustable portion of this case has been placed in its proper position it may be held there by means of a set-screw or by any other convenient device, and upon the proper adjustment of this part will depend, to a great extent, the efficiency of the instrument. Its efciency will also be very much affected by the thickness of the metal of which the angular portion A of the case is made, as it is an ascertained factth'at the efliciency of instruments of this character depends, to a great extent, upon the rapid condensation of the steam at the point where it mingles with the air or liquid which it is to ej ect 5 and hence it follows that if the point where the steam strikes the case is so thinas to permit the most rapid radiation of heat and at the same time the greatest cooling effect of the surroundingatmosphere possible the efliciency of the instrument will be largely increased thereby; and in order to. secure this result the thinportion of the metal must present the acute angle to the path of the steam or to the axis of the instrument above described.`

In exhausting air from vessels or pipes it will be found advisable to adjust the section A2 of the instrument that itsangular portion shall be very near to the end of the air-nozzle, in order that when the air in the vessel from which it is to be exhausted has become rarefied to some extent by exhaustion the more rapid condensation may cause a more perfect vacuum.

In the application of this instrument to pipes TENT @Trice or vessels for applying the brakes of cars it is important thatv means should be provided for maintaining a vacuum in such pipes or vessels after the steam has been sluit oli' from the ejector; and in order to provide for this there is placed in the chamber near the end where the air enters a valve, C, which is arranged to open inward, so that as steam is admitted to the instrument and a vacuum is formed therein the. valve will open and permit the air to pass out of the pipes and vessels, but will close the instant the steam is sluit ofi', and thus prevent the air from rushing in and destroying the vacnum.

As a considerable portion of the steam used will be condensed within the instrument, and as the water of condensation is liable to run down into the air-nozzle and thus to some extent injuriously at'ect the operation, and especially as this would be the case if it should be allowed to enter the pipes leading to the apparatus which applies the brakes, there is provided a small dri p-pipe which is attached to the chamber in which the valve C is placed, which has in its outer end a valve, D', opening outwardly so that when steam is shut o from the instrument it shall fall of its own gravity and per- Having thus described my invention, what l. An air-ejector having the angular portion of its case against which the steam impinges when passing the end of the air-eduction nozv zlel made ot' thinner metal than its other portions, substantially as and for the purpose set forth.

2.V The combination ofthe adjustable section A2 of the outer case of tbe ejector with the stationary section A thereof and with the air-discharge nozzle A1, the parts being arranged substantially as and for the purpose set forth.

3, The combination of a vacuum-valve with the air-eduction nozzle of an ejector, substantially as and for the purpose set forth.

4. An air-ejector combining in its construction an'outer adjustable case, an interior airdischarge nozzle, a vacuum-valve, and a drip valve for allowing` the water of condensation to pass from the instrument, substantially as and for the purpose set forth.

In testimony whereof I have signed my name to this specication in the presence of two subscribing witnesses. v

' JOHN Y. SMITH.

Witnesses:

D. P. HoLLowAY, W. BRADFORD. 

